This invention relates generally to a support assembly for a frame or rail assembly to connect a headboard and a footboard and, ultimately to support a mattress and box spring, and, more particularly, to an improved universal cross member support for a bed frame or bed rails.
Bed frames or bed rails are widely used to provide a support for the box spring and mattress and are of a relatively straightforward construction comprising a rectangular or square frame. In the case of bed rails, there are normally side rails that are wooden, rolled formed metal or angle iron and which connect to a headboard and a footboard. The side rails, the headboard and the footboard are interconnected so that the overall unit may be readily assembled and the unit is of predetermined dimensions so as to accept a standard box spring that is seated upon the frame.
Originally, the side rails would support laterally placed wooden bed slats that would cross the bed frame and support the box spring. Such wooden slats were strong enough to provide the necessary support to the box spring, however, they were generally troublesome, somewhat weak and were cumbersome to install and maintain in place, and required screws for assembly, particularly when moving the bed from one location to another. It was necessary to cut each slat to the particular width or space between the bed rails and the construction relied on the weight of the box spring and mattress to keep the slats in place.
As an alternate, therefore, there are currently used, one or more cross members that are constructed of steel angle iron and normally are L-shaped and are placed laterally across the frame spanning the side rails. Thus, as an improvement, the steel cross members replaced the wooden slats which made the consequent set up, construction and transportability considerable easier and the overall construction stronger. In addition, metal supports have also been used in conjunction with the wooden slats. Obviously, the steel cross members could be constructed of very heavy gauge steel so that adequate support could be provided for the box spring and mattress, however, the use of heavy gauge steel increases the cost of the cross member and additionally, adds to the overall weight of the structure. Therefore, although constructed of steel, the present cross members alone are not sufficient to provide the necessary amount of support for the box spring and mattress.
Thus, virtually all bedding manufacturers require the use of a rigid center support for the cross member, whether the construction is a bed frame or bed rails in order to insure the structural integrity of the box spring to prevent damage to that component. The use of such a rigid center support virtually precludes the use of a typical wooden slat or typical angle iron cross member without the use of a leg assembly that actually contacts the floor for the needed support to the cross member. Accordingly to solve the problem of a lack of adequate support, manufacturers universally turned to the use of a leg that relied on contact with the floor to add that support. An example of such solutions is shown in U.S. Pat. No. 5,502,852 of Fredman et al; U.S. Pat. No. 5,815,860 of Mitchell and U.S. Pat. No. 5,894,614 of Stroud.
It therefore became necessary to add a glide or glides to the leg of the steel cross member that spanned between the side rails to provide sufficient support to the cross member. The glide is generally affixed to a leg depending downwardly from the cross member and, in turn, the glide contacts the floor with a flat, planar bottom surface so that the cross member is supported on the floor and thus gives crucial support to the box spring and to the other components of the assembled bed. It should be noted, that while the glide is referred to as having a flat, planar bottom surface, that surface is an effective flat surface as the bottom of the glide may have its inner portion displaced upwardly such that the entire bottom surface is not really totally flat and planar. If totally flat, the tolerances would be considerably strict and thus, normally only an effective flat planar surface is formed in the bottom of such glides.
Obviously, with the use of a leg and glide to support the cross member, it is important that the overall length of the glide assembly, that is, the glide and the leg, be fairly precise with respect to the cross member. If the length of the glide assembly is too short, there is inadequate support for the cross member and the cross member will bow downwardly under the weight of the box spring until the necessary contact between the glide and the floor is established. If, on the other hand, the length of the glide assembly is too long, it causes the cross member to bow upwardly. In either case, the result is undesirable and can cause structural damage to the cross member and possibly to the box spring.
It is therefore necessary that the glide assembly be of the proper height and to that end, the glide itself is normally threadedly affixed to the leg so that the glide can be simply rotated by the user to raise and lower the glide to arrive at the proper desired height. The need for the adjustment is paramount in that the headboard and footboard, if there is one, is not a standard industry height above the floor and thus, the height of the frame and the side rails off the floor will differ from bed to bed so that a fixed height glide assembly would not be suitable to fit all beds universally. In addition, the bed may, from time to time, be moved about the room and the glide need to be readjusted due to irregularities in the floor itself to correct for high and low spots of the floor.
A further example of a cross member is shown and described in U.S. Pat. No. 4,080,674 of Fredman where the cross member includes a pair of supporting legs each of which have a vertically adjustable glide to insure that the cross member is adequately supported by the flooring without twisting or misalignment. Again, as explained, the solution is founded upon a reliance upon the floor to adequately support the center member.
Other examples of devices or vertically adjustable legs are shown and described in U.S. Pat. No. 5,502,852 of Fredman et al; U.S. Pat. No. 5,815,860 of Mitchell and U.S. Pat. No. 5,894,614 of Stroud, all of which have some means of adjusting the vertical length of a leg so that the overall bed frame can utilize the floor for support.
Typically, therefore, the glide has an upwardly extending threaded stem that mates with a corresponding threaded opening in the leg located in the desired position. The stem itself is generally small in diameter, about one quarter to one half inch diameter, for most applications, and its support in the leg is relatively secure and sufficiently strong for use as a support for the cross member when in place, i.e encountering compressive forces, however the overall glide assembly is not particularly strong when subjected to side forces and opened to the full extension of height.
Accordingly, when the headboard and footboard are moved from one location to another, such as for cleaning under the bed, and particularly when the box spring and the mattress are in position upon the bed frame, the glide drags on the floor as the bed is moved. Where the floor is covered, for example, with carpeting, the dragging causes twisting of the glide assembly and can easily lead to a breaking of the leg from the cross member and/or ever damage to the box spring.
Too, the cross member is, as indicated, generally a steel L-shaped member and is easily twisted through the influence of a bending of the glide member so that damage to the cross member is a good possibility. Added to that weakness, is the fact that many cross members are coupled together at the center point between the two side rails, that is, the cross member is generally extended in two sections inwardly from the side rails and is coupled together at or near the center of the span between the side rails by some clamp or other coupling device to compensate for the varying widths of the headboards and footboards.
Thus, the center of the span between the supporting side rails is already a vulnerable spot where the cross member is weak, however, adding to that weakness is the use of a coupling at that center spot where the two individual cross member are joined together by a clamp. In short, the glide assembly that supports the cross member is in a most vulnerable position with respect to being damaged or to damaging the cross member and the box spring by the user moving it from one location to another or by simply having the height adjustment incorrectly set.
Obviously for the user or installer, this is a severe problem as it creates the necessity to obtain another bed rail or support system as the breaking of a leg is generally not repairable since the components are stamped metal parts that are riveted together. It would certainly be advantageous to avoid the problem altogether so that the bed frame is not subject to the breakage problem herein outlined.
Another problem exists in the construction of a cross member in that the actual width or span between the side rails may have a variance and thus there may need to make an adjustment in the length of the cross member to insure that it properly aligns with the particular fitting or bracket in the side rails. The difficulty is particularly significant where the cross member is assembled by fitting into brackets or the like in the side rails as the length must be accurate to make the proper fitting possible. Thus, presently there are many ways to attach the cross members to a side rail that are non-standard devices.
Accordingly, it would be advantageous that the length of the cross member be designed so as to be adjustable to make certain its assembly to the side rails can be made easily and accurately. An attempt at solving that problem is shown in the aforementioned disclosures of U.S. Pat. No. 5,502,852 of Friedman et al; U.S. Pat. No. 5,815,860 of Mitchell and U.S. Pat. No. 5,894,614 of Stroud. However, again, the center of the cross member is already the weakest area of the cross member and the addition of a sliding connection at that point adds to the weakness of the cross member. It would be advantageous to allow the cross member to have a width adjustment without detracting from the overall integrity of that cross member.